Charles Frederick "Boots" Day (born August 31, 1947) is an American former professional baseball outfielder. He played in Major League Baseball (MLB) for the St. Louis Cardinals, Chicago Cubs, and Montreal Expos. Day is currently the bench coach for the Evansville Otters of the Frontier League. A native of Ilion, New York, Day played Major League Baseball for all or parts of six seasons (1969–74), with the bulk of that time spent with the Montreal Expos. He threw and batted left-handed, stood 5 feet 9 inches (1.75 m) tall and weighed 160 pounds (73 kg).